what is the minimum saadc working freq,5us?

[wen]

i use the saadc as well as ble.the saadc dose not working on 200k hz(5us) as the Product Specification says.what is the wrong?

[Ole Bauck]

The SAADC can have acquisition time from 3us to 40us depending on the source resistance, see here. What is the configuration of your adc and what are you measuring? What is the source resistance? For which frequency does it work?